铅芯隔震橡胶支座参数对连续梁桥地震响应的影响

Inf luence of Lead Rubber Bearing Isolator Parameters on Seismic Response of Continuous Girder Bridge

采用有限元软件ANSYS建立4跨连续T梁桥有限元模型,基于非线性时程分析法研究了铅芯隔震橡胶支座参数对桥梁地震响应的影响规律。研究结果表明:桥墩的墩梁纵桥向相对位移最大值随屈服前刚度与屈服后刚度的增大呈逐渐减小的趋势;桥墩墩底纵桥向弯矩最大值随屈服前刚度的增大呈先减小后增大的趋势,而随屈服后刚度的增大呈先增大后减小的趋势;随着铅芯隔震橡胶支座等效阻尼比、铅芯屈服力的增大,桥墩墩底纵桥向弯矩最大值呈先逐渐减小后逐渐增大的趋势。

A finite element model of the four-span continuous girder bridge with T-shaped girder was established by the finite element software ANSYS. The influence of lead rubber bearing isolator parameters on the seismic response of bridge were studied on the basis of nonlinear time history analysis method. The research results show that with the increase of pre-yield stiffness and post-yield stiffness, the maximum longitudinal relative displacements of pier-girders decrease. With the increase of pre-yield stiffness, the maximum longitudinal bending moments at the bottom of piers decrease firstly and then increase. While with the increase of post-yield stiffness, the maximum longitudinal bending moments at the bottom of piers increase firstly and then decrease. With the increase of the equivalent damping ratio and load-yield force of lead rubber bearing isolator, the maximum longitudinal bending moments at the bottom of piers decrease gradually and then increase.